The game is laggy, even with my Fermi 480. I should be able to have everything turned up 100% and get great framerates. However, I had to turn some items down and its still very choppy/laggy. Something make me think something else is running in the background because I often see what looks like a little box pop up in various parts of the middle screen. Aside from the lag and Steam's [censored] with making midnight buyers wait for Westcoast to roll midnight. The game seems fine.

Oh ya i didn't notice a vert. sync option in video settings which I believe is supposed to relieve alot of the taring I've been seeing. I'm sure they'll patch this game within a week to fix the lag and tare.

Graphics card isn't everything, what else does your PC have?

Ive got a pretty good machine:

CPU:Black edition Phenom II 965 Quadcore w/Corsair H50 liquid cooler
MB:MSI K9N2 Diamond
GPU:Nvidia geforce fermi 480 sc
Ram:Crucial x4 2gb sticks 1066MHZ (8 gigs)
Case:Coolermaster HAF 932 fullsize
Powersupply:Kingwin 800watt modular
OS:Windows 7 64-bit home basic

I experience lag, too.
Must be something wrong with the game.
I turned all the settings down as low as they'd go and I still experience low framerate.

I don't have a stellar machine, but the game recognized 'high' settings for me when I first started it up. 2.4ghz dual, 9800gt nvidia, 4gb ram, etc.
I guess I'll have to wait for a patch or something.

Yeah, we'll definitely need to know the rest of your specs. CPU and RAM are probably most pertinent in this case. I've heard some people say that, for whatever reason, New Vegas seems to use a startlingly low amount of their video card's memory, so the lag is probably coming from your CPU and RAM which are being made to do the rest of the work.

Of course, given those stats, it doesn't seem like that's the case. (Sorry, started writing before you replied. ) I think it has something to do with the way the game utilizes quad-core CPUs, which is another problem I've heard. The thing is, though, I have the exact same CPU as you but with different cooling, and I'm getting normal framerates so far, so maybe it's just a driver thing. Do you have the newest drivers? I just built my computer a couple of weeks ago so the drivers will be almost the newest, if not the newest. Maybe that will help.

Well considering the consoles are running it with the equivalent of a 7600 and you have 9800,(I had one too it was a very good GPU) You should be able to run this thing up pretty high also. Consoles are 4 generations behind in GPU's.

Yes the game is laggy for me as well. Frame rate drops galore. The game detected ultra settings for me, but it still drops to low 20's even when i lower the graphics. Hopefully a patch soon. I have a radeon hd5750 with 10.9 catalyst.

Just updated the Graphics driver from v258 to v260 on my Fermi 480, It didnt help at all. I've finally come to the first big fight in the small town and its so laggy and jumpy I can't play because I cant hit anything while shooting. Please Bethesda, Nvidia, Steam, whoever fix this quickly. The game is UNPLAYABLE unless i'm just wandering around looting houses.

Seriously, i'm getting 1-3 FPS during the fight and while running around before the fight maybe 15-40(in various intervals) As another poster said, I too am getting ultra high recommended default settings. The only thing I change is the recommended Resolution to suite my 27" gaming monitor.

It has become clear to me after reading these forums that nobody knows what lag is. Lag = latency, which is 99.99999% of the time only an issue in online games, though sometimes a bug or something could be causing it in a single player game. Choppiness/framerate drop isn't lag. It's exactly that, low framerate.

LAG FIXED!

Switch the HDR to Bloom under options in the options menu before yous start the game. This is a temporary fix till they fix HDR, this will fix most problems people have been having with lag, seeing dots and boxes, and taring, and from what i can tell it makes the game more stable so it doesn't crash as much for those of you who have been having this problem.

Theres already a huge thread on this http://www.gamesas.com/index.php?/topic/1122285-game-runs-very-choppy/page__st__40 and i feel your pain, you and I are in the same boat as a lot of other people are.

It's gotta be the fermi drivers. I backdated to 260.63 and it helped although there is still flashing HDR floating random lights.